Clutch; Chain Brake; Checking Function - Stihl 019 T User Manual

3.2

Clutch

Troubleshooting chart - see "Standard
Repairs, Troubleshooting" handbook.
- Remove chain sprocket - see 3.1.
• Pull boot (1) off the spark plug.
- Unscrew the spark plug (2).
• Push the locking strip (1)
0000 893 5903 into the cylinder.
STIHL 019 T
• Unscrew the clutch from the
crankshaft in the direction of the
arrow (left-hand thread).
- Disassemble and reassemble
the clutch - see "Standard
Repairs, Troubleshooting"
handbook.
• Screw clutch onto crankshaft
and torque down to 50 Nm
(37 Ibf.ft).
- Remove locking strip from
cylinder.
- Install spark plug and torque
down to 25 Nm (18.5 Ibf.ft).
Important: If spark plug has a
separate terminal nut, make sure
that it is properly tightened down.
- Fit spark plug boot.
- Install the chain sprocket -
see 3.1.
3.3

Chain Brake

3.3.1

Checking Function

The chain brake is one of the most
important safety devices on the
chainsaw. Its efficiency is measured in
terms of braking time, i.e. the time that
elapses between activating the brake
and the saw chain coming to a
standstill. The shorter the braking time,
the better the efficiency and protection
offered against being injured by the
rotating chain.
Contamination (with chain oil, chips,
fine particles of abrasion, etc.) and
smoothing of the friction surfaces of the
brake band and clutch drum impair the
coefficient of friction. This, in turn,
reduces the frictional forces and thus
prolongs the braking time. A fatigued or
stretched brake spring has the same
negative effect.
- Start the engine.
- With the chain brake activated
(locked), open throttle wide for brief
period (max. 3 seconds) the chain
must not rotate.
- With the chain brake released, open
throttle wide and activate the brake
manually - the chain must come to an
abrupt stop.
Note: The braking time is in order if
deceleration of the saw chain is
imperceptible to the eye.
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